Background: Fluoride plays an essential role in maintaining good dental health, especially during childhood when permanent teeth are forming. Fluoride helps prevent tooth decay by promoting tooth remineralisation and preventing tooth demineralisation. There are no data on the actual intakes of fluoride in New Zealand children 5 years or older.

Objective: To trial the feasibility of measuring actual fluoride intakes of 9-10-year-old New Zealand children living in the fluoridated and non-fluoridated cities of Dunedin and Timaru, respectively.

Design: This study aimed to recruit 10 children from each city. Dietary fluoride intake was measured by 24-hour diet records and duplicate diets. Expectorated toothpaste and saliva samples were used to measure fluoride from toothpaste ingestion. Twenty-four-hour urine samples were collected to analyse urinary fluoride excretion.

Results: The mean (SD) total daily fluoride intake of Dunedin (n=10) and Timaru (n=10) children was 1.7 (0.6) mg/day and 1.2 (0.6) mg/day, respectively, with 1.0 (0.4) mg/day and 1.0 (0.5) mg/day contributed from toothpaste; the AI for fluoride is 2mg/day. Fractional urinary fluoride excretion for Dunedin and Timaru children was 23% and 21%, respectively.

Conclusion: Diet records, expectorated toothpaste and saliva, and 24-hour urine samples are feasible methods to determine the daily fluoride intakes of 9-10-year-old children. Toothpaste was the primary source of fluoride for children in both cities and fluoridated water was an important source of fluoride for Dunedin children.